Method and machine for making cables



Jan. 15, 1963 A. BRAATEN 3,073,104

METHOD AND MACHINE FOR MAKING CABLES I n ventor A BRAATEN A ttom ey Jan. 15, 1963 A. BRAATEN METHOD AND MACHINE FOR MAKING CABLES 3 Sheets-Sheet 2 Filed Dec. 22, 1958 FIG.Z.

Inventor w N WA. M9 w Am Jan. 15, 1963 A. BRAATEN METHOD AND MACHINE FOR MAKING CABLES 3 Sheets-Sheet 3 Filed Dec. 22, 1958 Inventor BRAATEN Attorney United States Patent Ofifice 3,073,104 Patented Jan. 15, 1963 METHOD AND MACHINE FOR MAKING CABLES Amnnd Braaten, Oslo, Norway, assignor to International Standard Electric Corporation, New York, N.Y., a corporation of Delaware Filed Dec. 22, 1958, Ser. No. 782,237 Claims priority, application Norway Dec. 24, 1957 4 Claims. (Cl. 57-12) The present invention relates to a method for making Wire rope or cables of steel and/or metal, for the sake of convenience referred to below as metal wire cables.

A number of different types of stranding machines for the manufacture of metal wire cables comprising one or more layers of metal wires are generally known. The types employed for stranding a single layer comprises stranding machines with pay otf bobbins mounted in a stationary rack for the manufacture of cable, with or without floating bobbins, for instance buncher machines, braiding machines with flyer and machines with take-up reels mounted in a rotating cradle, and all the types of stranding machines provided with bobbins or reels mounted in rotating parts.

All known types of stranding machines for the manufacture of metal wire cable consisting of several layers of metal Wires are furnished with reels which are placed in rotating members and which contain definite lengths of individual metal Wires. The use of reels containing individual Wires is very unsatisfactory since this results in poor utilization of the machinery due to the fact that replacement of the reels is very time-consuming and also since this results in a large percentage of wasted wire, as the relatively short wire lengths which are left on the reels after the desired cable length is stranded, hardly can be utilized. The great number of reels employed for stranding several layers of metal wires, necessarily results in very large machines and the size of the rotating members limits the rotating speed and thereby the output of finished cable.

The object of the present invention is to provide a method and a stranding machine for the manufacture of a cable having several layers of metal wires, for making possible a considerably greater output per time unit as compared to the output by previously known methods.

The method according to the invention possesses considerable advantages as the machinery is relatively simple, it is easy to operate and can be utilized more efficiently, especially as waste of remaining .lengths of wire is avoided.

The invention concerns a method for the manufacture of metal wire cables comprising at least two layers of steel and/or metal wires by using stranding rotors of a type where theup-to-then finished cable is taken up by the stranding rotor. The characteristic feature of the invention is that the stranding rotor where the up-to-then finished cable is taken up serves as pay-off device for the stranding rotor wherein the next layer of wires is to be applied. Two stranding rotors may be used alternately applying the desired number of wires or several stranding rotors may be used, of which each one separately applies a layer.

The invention also concerns a stranding machine for use in connection with the said method. The stranding machine is characterized by mechanical or electrical synchronizing equipment between pairs of stranding rotors. The synchronizing equipment causes two stranding rotors to rotate at nearly the same speed of rotation such that the stranding rotor which serves as pay-off equipment provides the necessary retrograde motion of the unto-then finished part of the cable which is supplied to the stranding rotor when the next layer of wire is applied. The stranding rotors each of which may be provided 2 with a permanently fitted reel, are particularly designed for high speeds.

The method according to the invention is not limited to stranding of a certain number of layers of metal Wire or to comprise a certain maximum number of wires in each layer. The largest known stranding machines which are generally used in the cable industry are designed for applying four layers of metal wire on a core, where each layer respectively consists of 6, 12, 18 and 24 wires. These machines totally comprise 60 reels which are mounted in rotating members. It requires on the average 3-5 minutes to replace each one of the heavy reels. Various improvements have been suggested in order to reduce the time necessary for replacing the reels, but in spite of these improvements, it is obvious that replacement of the reels to a great extent reduces the effective use of the machines even whena large crew is used. Waste of wire by this type of machine is normally considered to be approximately 1% of the total quantity of wire used, and thus this represents a considerable increase in the price of the product.

The invention will in detail be described in connection with preferred embodiments shown on the drawings FIG. 1 shows two stranding rotors, 1 and 2, for instance of the type which is described in detail in connection with FIG. 3. Stranding rotors which may have permanently fitted reels, are especially designed for high speed of rotation. A core is supplied with the first layer of wires in one of the stranding rotors, for instance 1. The take-up reel is designed such that it can take up a great length of stranded cable. When the desired length of cable is stranded in this operation or when the takeup reel is full, the stranding rotor 1 is stopped and the end of the cable is pulled out from rotor 1 and inserted directly into the second stranding rotor 2, together with the desired number of wires which are to constitute the next layer of metal wires. The stranding rotor 2 is thereafter started and the next layer of metal wires is applied in the opposite direction at the same time as the cable is payed off the reel of the stranding rotor 1 and pulled into the stranding rotor 2. It clearly appears from the figure that the machinery is arranged in such a manner that the so-far finished part of the cable may be guided alternately, and directly from one stranding rotor to the other stranding rotor until the desired number of layers are applied, the desired number of individual metal wires may be applied in infinite lengths as the wire of an almost empty coil is welded to the wire of a new coil.

When the desired number of layers has been applied, the finished metal wire cable is spooled onto a conventional storage drum in a spooling machine.

The stranding rotors are made to revolve at approximately the same speed by means of synchronizing arrangements S, which may be of any electrical or mechanical type.

FIG. 2 shows machinery with four high speed stranding rotors 5, 6, 7 and 8. This arrangement is particularly designed for stranding of cables consisting of the following layers: Core and six wires (or a steel core consisting of seven wires), 12 wires, 18 wires and 24 wires. The 6 wires and a core are stranded in the first stranding rotor 5. When the take-up reel in the first stranding rotor is filled up, the so-fa-r finished part of the cable is guided into the next stranding rotor 6 together with the individual Wires, whereupon the stranding of the next layer is applied at the sametime as theca-bleis spooled off the reel in the stranding rotor and is pulled into the stranding rotor 6. This procedure is continued for 7 and 8 until all layers are applied, after which the finished cable is spooled from rotor 8 onto a storage drum in a spooling machine. It is quite obvious that this method facilitates a very effective use of the machinery. By designing the individual stranding rotors, which are made for taking up layers with the least number of wires, for greater speeds than the other individual stranding rotors, it is obvious that the equipment can beused very efliciently.

The stranding rotors are in pairs arrangedto rotate with the same speed by means of electrical or mechanical synchronizing equipment S arranged for connection between two adjacent stranding rotors.

FIG. 3 shows a type of high speed stranding rotor, especially suitable for praoticingthe method according to the present invention. The rotor 10 is mounted on the bearing supports 11 and Hand is driven by means of gears, chains or. other known power transmission means 13. A

reel 14 which preferably is permanently attached to a shaft 15 is arranged concentrically to the rotor shaft. The reel with shaft is constructed as a single unit particularly designed for high speed. The reelshaft is supported in the. rotorin such a manner that the reel can rotate around its own axis, at the same time as it is shifted back and forth in directions lengthwise of the axis. The reelshaft has, an extension 16 which is associated with guiding means 17, designed to shift the shaft and reel back and forth in order to spool'up the cable properly. The guiding means 17 is only shown schematically in FIG. 3 as such arrangements are well-known, a suitable guiding and reciprocating structure for this purpose being shown in U.S..Patent.1,867,688, and in the corresponding Bulletin 110146 of the Watson Machine Company of Paterson, New. Jersey, for traverses, typeC, and guides. The

reelshaft is coupled to a gear 153 or any other reversible In order to provide a certain lay the power transmission means of the rotor and the reel are arranged such that a.

previously determined and adjusted relation between the linear speed of the cable and the speed of rotation of the rotor is constant, the speed of rotation of the reel being controlled by the control means 23' which may be applied to the drive of rotor 10 as indicated at 23' or alternatively to the driving means associated with drive gear 13 of shaft 16. A number of known speed controls 4 means common in the field of servo-mechanisms may be used, for example, as shown in FIGURE 8.3-3 of the book Servo-Mechanisms and Regulating System Design by H. Chestnut and C. W. Mayer, volume 1, John Wiley and Sons,.inc., New Yorlo It: clearly appears from the figure that machinery ofthistype is particularly suitable for high speeds, since the machinery is designed with a permanently fitted reel which is carefully balanced.

It is obvious that the invention is not limited to relate to the type of stranding rotors as described in FIG. 3. A stranding rotor of a type where a reel is supported in a revolving cradle may also be used. The stranding rotors can, of course, be furnished with capstans. A simple design of the many possiblesynchronizing arrangements which may be used, is gear units which may be connected between pairs of stranding rotors.

What is claimed is:

1. A method of manufacturing a cable having a plurality of layers of wires on a cable core using stranding rotors having associated storage reels comprising thev steps of feeding the strands of wire and the cable core into a first strandingrotor to-produce a partially finished stranded cable, winding the partial cable onto the reel of.

the stranding rotor, feeding this partial cable from the reel of saidfirst stranding rotor together with additionalv stranding wires into a second stranding rotor whereby the reel of said'first rotor serves as a pay-off device for the second stranding rotor, synchronizing the rotation of saidfirst and second rotors to produce a predetermined lay of said stranded cable and winding the resultantinner reel member rotatably mounted within said rotor member and coaxial therewith for taking upandpaying out stranded lines, first means for rotating said rotor'men L her, second means for rotating said reel member, and third means coupled to said second means and to said reel member for axially translating said reel member relative' to said rotor member in synchronism with therotation of said reel member.

4. A stranding machine according to claim 3 and including fourth means coupledto saidsecond rotating means for varying the operation thereof to enable said reel member to alternately take up and pay out a length.

of stranded cable.

References Cited in the file of this patent j UNITED STATES PATENTS' 1,747,769 Pullman et al. Feb. 18, 1930 1,956,730 Reichelt May 1,. 1934. 2,058,234 Johannessen Oct. 20, .1936 2,780,906

Fewtrell'et Feb, 12, 1957 

1. A METHOD OF MANUFACTURING A CABLE HAVING A PLURALITY OF LAYERS OF WIRES ON A CABLE CORE USING STRANDING ROTORS HAVING ASSOCIATED STORAGE REELS COMPRISING THE STEPS OF FEEDING THE STRANDS OF WIRE AND THE CABLE CORE INTO A FIRST STRANDING ROTOR TO PRODUCE A PARTIALLY FINISHED STRANDED CABLE, WINDING THE PARTIAL CABLE ONTO THE REEL OF THE STRANDING ROTOR, FEEDING THIS PARTIAL CABLE FROM THE REEL OF SAID FIRST STRANDING ROTOR TOGETHER WITH ADDITIONAL STRANDING WIRES INTO A SECOND STRANDING ROTOR WHEREBY THE REEL OF SAID FIRST ROTOR SERVES AS A PAY-OFF DEVICE FOR THE SECOND STRANDING ROTOR, SYNCHRONIZING THE ROTATION OF SAID FIRST AND SECOND ROTORS TO PRODUCE A PREDETERMINED LAY OF SAID STRANDED CABLE AND WINDING THE RESULTANT STRANDED CABLE ONTO THE REEL OF SAID SECOND STRANDING ROTOR. 